Prognostic nutritional index (PNI), based on serum lymphocyte counts and albumin levels, has been introduced as a simple and easily measurable biomarker, representing the nutritional and immunological status of cancer patients. However, the nutritional and inflammatory conditions can be different between pre- and post-operative statuses because of eradication of primary tumors, and major surgeries can influence the general condition and immune reaction of a host. Here, we aimed to examine the prognostic role of prognostic nutritional index (PNI) dynamics in the pre- and postoperative periods in patients with renal cell carcinoma (RCC) who underwent radical nephrectomy (RN).
We analyzed 324 patients with RCC who underwent RN. Overall population was classified into 4 groups according to 4 types of pre- to postoperative PNI dynamics as follows: Group 1 (low → low PNI), 2 (low → high PNI), 3 (high → low PNI) and 4 (high → high PNI). The level of PNI was calculated using the following formula: 10 × serum albumin level (g/dL) + 0.005 × absolute lymphocyte counts in blood (/mm3). Primary and secondary endpoints were cancer-specific survival (CSS) and overall survival (OS), respectively.
Patients with higher pre- and postoperative PNI (> 45) had better survival outcomes than those with lower pre- and postoperative PNI (≤ 45). Notably, patients in Group 4 showed the best CSS and OS rates, whereas patients in Group 1 had the worst survival outcomes. Furthermore, PNI dynamics was identified as an independent predictor for CSS and OS outcomes, in addition to pre- and postoperative PNI, tumor size, and pathologic T (pT) stage. Patients with localized RCC (≤ pT2) showed significant differences in both CSS and OS estimates, while patients with advanced pT stage (≥ pT3) demonstrated a difference only in OS outcomes, according to PNI dynamics.
In summary, PNI dynamics in pre- and postoperative status was identified as a valuable predictor of survival outcomes in patients with RCC undergoing RN. Our study is the first that provides the independent prognostic importance of dynamics of nutritional status for patients with RCC.
Samsung Medical Center, Sungkyunkwan University School of Medicine.
Korea Health Industry Development Institute (KHIDI)
All authors have declared no conflicts of interest.